Over the last few decades, the electronics industry has undergone a revolution by the use of semiconductor technology to fabricate small, highly integrated electronic devices. In most fabrication lines, chemical vapor deposition (CVD) systems are commonly used to deposit films on semiconductor wafers. A typical CVD system includes: (1) a deposition chamber; (2) gas sources; (3) inlet lines for feeding gas from the gas sources into the deposition chamber; (4) a heating block for heating the wafers on which the film is to be deposited; (5) an outlet line; and (6) a vacuum source for evacuating waste byproducts from the deposition chamber through the outlet line.
During a fabrication run, waste by-product typically accumulates on various components of a CVD system, such as the chamber walls, inlet and outlet lines, and heating block, for example. Excessive accumulation on the CVD heating block in particular can have a deleteriously impact on the fabrication of semiconductor wafers. As a result, the CVD system is periodically shut down and the heating block is cleaned.
Cleaning of the heating block typically involves accessing the heating block, for example, by disassembling the CVD system, and sanding the heating block to remove the accumulated waste byproduct. Prior to sanding the heating block, the block must be allowed to cool to a temperature which is conducive to sanding. In a typical system, the temperature of a heating block may have to fall, for example, from about 500.degree. C. to about 75 to 80.degree. C. prior to sanding. The total time for the cleansing process depends on the severity of the accumulation as well as on the size and temperature of the heating block. Using conventional techniques, a typical cleansing process can often take from 4 to 6 hours or more. The downtime incurred as a result of the cleansing process has a significant impact on production and, accordingly, is desirably minimized.